Poor Fuel Economy

Fuel economy is noticeably lower than expected. Customer detects a significant reduction in fuel mileage.

POSSIBLE CAUSE ACTION


EGR malfunction, Check EGR system in "Testing
Flange gasket leaking, Procedures"
solenoid or thermo valve
malfunctioning



Ignition timing Check Ignition Timing in "Adjustment
Procedures"



Spark timing Check Spark Controls in
"Testing Procedures"




Air management valves Check Air Injection system in
"Testing Procedures"





Restricted exhaust Check Catalytic Converter in
"Testing Procedures"